AU2005203344B8

AU2005203344B8 - Fastening element

Info

Publication number: AU2005203344B8
Application number: AU2005203344A
Authority: AU
Inventors: Sven Dietze; Rene Ortler
Original assignee: Hilti AG
Current assignee: Hilti AG
Priority date: 2004-08-23
Filing date: 2005-07-29
Publication date: 2009-07-23
Anticipated expiration: 2025-07-29
Also published as: PL1630428T3; TW200615466A; AU2005203344A1; AU2005203344B2; CN100510434C; TWI293666B; EP1630428A1; US7520710B2; CN1740577A; US20060041226A1; DE102004040701B3; DE502005003711D1; EP1630428B1

Description

AUSTRALIA PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT ORIGINAL Name of Applicant/s: Hilti Aktiengesellschaft Actual Inventor/s: Rene Ortler and Sven Dietze Address for Service is: SHELSTON IP 60 Margaret Street Telephone No: (02) 9777 1111 SYDNEY NSW 2000 Facsimile No. (02) 9241 4666 CCN: 3710000352 Attorney Code: SW Invention Title: FASTENING ELEMENT The following statement is a full description of this invention, including the best method of performing it known to me/us: File: 46396AUP00 -2 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to fastening elements and, in particular, to drive-in fastening elements. 5 2. Description of the Prior Art Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field. Fastening elements of the type described above, such as nails, bolts and the like 10 are usually formed of steel and are used, in fastening technology for securing objects to hard materials such as concrete, metal, and stone. The drive-in process of such fastening elements is carried out with high speed, and the fastening elements are driven-in percussively or otherwise, e.g., with combustion-driven tools. German Publication DE 101 19 800 A l discloses a fastening element having a 15 head and a stem adjoining the head and provided, at its end remote from the head, with a tip. The stem has a first spherical section that tapers toward the tip, and a second section that adjoins the first section and extends in the direction toward the head. The spherical first section and the following second section are provided, at least partially, with a knurl profile. This profile increases friction and, therefore, abrasion of the material. 20 U.S. Patent No. 5,127,785, from which the present invention proceeds, discloses a nail for suspending of supports and that has a stem having a first bullet-shaped or spherical section decreasing toward the tip, and a second cylindrical section. The head, which is provided at the end of the stem remote from the tip, has the same diameter as the second cylindrical section. The stem is provided with a deeply cut-in thread profile 25 that ends in front of the tip and that only partially surrounds the rear stem region. The thread serves for removal of the material produced by the drivable-in nail and increases the friction between the nail and the constructional component. The drawbacks of such fastening element consists in that with thread grooves having the same depth and with an intermediate gradient, at a very rapid drive-in -3 displacement, which is carried out, e.g., with a combustion-driven setting tool, the thread does not lead to rotation of the nail but rather acts as a grater, causing substantial abrasion. The abrasion reduces the holding forces of a nail in the constructional component. 5 It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative. Accordingly, an object of the present invention in its preferred form is to provide a fastening element in which the foregoing drawbacks are reduced. Another object of the present invention in its preferred form is to provide a 10 fastening element with good holding characteristics in a hard material, e.g., concrete or steel. Summary of the Invention According to the invention, there is provided a linearly driven-in fastening element, comprising: a stem having a tip at one end thereof; a head arranged at an end of 15 the stem opposite the tip, the stem having a first bullet-shaped section extending from the tip in a direction of the head, and a second section adjoining the first section at an end of the first section remote from the tip and extending in the direction of the head; and a thread profile provided on the stem, the thread profile having, on the second section, a constant steep gradient with a lead angle from 500 to 74* and, on the first 20 section, a gradient that increases from the lead angle of the second section toward the tip, with a lead angle at a half of a length between the tip and the end of the first section remote from the tip amounting to at least 75*. Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising", and the like are to be construed in an 25 inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to". Preferably, the thread profile has at least three and, more preferably, at least ten profile grooves. As the fastening element is being driven into a constructional component, the grooves increase the rotation of the fastening element. Very good -4 results are obtained with fastening elements having a thread profile with a number of grooves from ten to fifteen. Preferably, the profile grooves are uniformly distributed over the circumference of the profiled region of the stem. 5 It is preferable that the profile depth of the profile grooves in the second section is essentially constant (within manufacturing tolerances) and has a value that lies within a range from .04mm to .15mm. E.g., the profile grooves can have a constant depth of .06mm in the second section. In the first section that adjoins the second section, the depth of the profile grooves preferably decreases toward the tip and lies in a region 10 between .01mm and .1 5mm E.g., with a constant depth of .06mm of the profile grooves in the second section, the profile depth of the profile grooves in the first section decreases from the depth of .06mm to a minimum of .0lmm toward the tip. With these profile depths, a good compromise is achieved that, on one hand, insures a good rotation of the fastening clement and, on the other hand, causes only a minimal reduction of the 15 drive-in energy. It is advantageous when the profile width of the profile grooves in the second section is essentially constant (within manufacturing tolerances) and has a value that lies within a range from .1mm to .8mm. E.g., the profile grooves can have a constant width of .5mm in the second section. In the first section that adjoins the second section, the 20 width of the profile grooves preferably decreases toward the tip and lies in a region between .8mm and .05mm. E.g., with a constant width of .5mm of the profile grooves in the second section, the profile depth of the profile grooves in the first section decreases from the depth of .5mm to a minimum of .2mm toward the tip. These profile widths improve the effect of the rotation of the fastening element at high drive-in speeds. 25 It is an advantage of at least a preferred embodiment of the fastening element that it can be drilled into a constructional component even at high drive-in speeds of more than 50m/sec, which are attained when the fastening element is driven-in with a combustion-driven setting tool. The rotation of the driven-in fastening element reduces high abrasion of a material of the constructional component. As the fastening element 30 is driven in, a thread profile is formed in the constructional component that increases the holding effect of the fastening element in the constructional component because of an -5 improved form locking connection of the fastening element with the constructional component. In metallic constructional components, for example, an embodiment of the fastening element, which has a stem diameter of 4mm, permits to obtain a holding value of 15 KN, with a middle drive-in depth of 12mm. 5 The novel features of the present invention, which are considered as characteristic for the invention, are set forth in the appended claims. The invention itself, however, both as to its construction and its mode of operation, together with additional advantages thereof, will be best understood from the following detailed description of the preferred embodiment, when read with reference to the accompanying 10 drawings. Brief Description of the Drawings: A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: 15 Fig. I a side view of a fastening element according to the present invention; Fig. 2 a cross-sectional view along line Il-Il in Fig. 1; and Fig. 3 a cross-sectional view along line 11-11 in Fig. I Detailed Description of the Preferred Embodiments A fastening element 10 according to the present invention, which is shown in 20 Figs. 1-3, is forced as a nail having a head 14, a stem I1 adjoining the head 14, and a tip 13 provided at the end of the stem I 1 opposite the head 14. The stem has two sections, a first spherical section 2 1 that directly adjoins the tip 13, and a second, substantially cylindrical section 22 that extends from the end 24 of the first section 21, opposite the tip 13, to the head 14. The region of the second section 22, which is adjacent to the first 25 section 21, is provided with a thread profile 15 that also extends over the first section 2 1. In the embodiment shown in the drawings, the thread profile 15 has twelve profile groove 16. In the region of the second section 22, the thread profile 15 has a constant steep gradient with a lead angle P2 of 600. The angle is defined from an equation tan P = Ph/-id, where Ph is the thread profile gradient and d is the diameter of 30 the fastening element 10. In the region of the first section 2 1, the gradient and the lead -6 angle P increases toward the tip 13. Thus, e.g., at a half length 17 between the tip 13 and the opposite end 24, the lead angle P, is greater than 75'. In the embodiment shown in the drawings, the thread profile 15 extends up to the tip 1 3 and, in the frontmost region 23 of the first section 21 adjacent to the tip 13, extends almost coaxially to the 5 longitudinal extent of the fastening element 10. It should be pointed out that the frontmost region 23 of the first section 21 can also be formed without a thread profile. The profile grooves 16 have, in the region of the second section 22, a constant profile or groove depth t of .06mm and a constant groove width b of .5mm, with the diameter of the second section 22 being equal 4mm. In the first section 21, the profile or 10 groove depth t decreases from .06mm in the region of the end 24 adjacent to the second section 22 to .01mm in the region of the tip 13. The groove width b likewise decreases from about .5mm at the end 24 to .2mm in the region of the tip 13. Though the present invention was shown and described with reference to the preferred embodiment, such is merely illustrative of the present invention and is not to 15 be construed as a limitation thereof, and various modifications of the present invention will be apparent to those skilled in the art. It is, therefore, not intended that the present invention be limited to disclose the embodiment or details thereof, and the present invention includes all variations and/or alternative embodiments within the spirit and scope of the present invention as defined by the appended claims. 20

Claims

2. A fastening element according to claim 1, wherein the thread profile has at least three profile grooves.
3. A fastening element according to claim I or claim 2, wherein the thread profile has at least ten profile grooves. 15 4. A fastening element according to claim 2 or claim 3, wherein the profile grooves are uniformly distributed over a circumference of the stem.
5. A fastening element according to any one of the claims 2 to 4, wherein each profile groove has a substantially constant depth in the second section and is selected in a range from .04mm to .15mm. 20 6. A fastening element according to any one of claims 2 to 5, wherein each profile groove in the first region has a depth which decreases toward the tip and lies within a range between .01mm and .15mm.
7. A fastening element according to any one of claims 2 to 6, wherein each profile groove has a substantially constant width in the second section and is selected in a range 25 from .01mm to .8mm.
8. A fastening element according to any one of claims 2 to 7, wherein each profile groove in the first region has a width which decreases toward the tip and lies within a range between .8mm and .05mm. -8
9. A fastening element substantially as herein described with reference to any one of the embodiments of the invention illustrated in the accompanying drawings and/or examples.